This invention relates to a mat of the type where a natural or synthetic rubber backing sheet is secured to the back of a fabric layer leaving a rubber border extending beyond the fabric layer, and to a method of manufacturing such a mat.
It is well known to lay floor mats at the entrance of buildings such as dwellings and offices, for scraping and wiping the undersides of the footwear of persons entering the buildings. Scraper mats may also be employed for reducing levels of mud carried on footwear in locations such as building sites and farms. Such mats have a natural or synthetic rubber backing sheet to prevent the passage of dirt through the mat. The backing sheet extends beyond the fabric to form a border, which defines the edge of the mat.
It is known to provide such mats in the form of a continuous roll of matting, which may be cut to the required length to form a mat. The continuous roll of matting is provided with rubber borders at each longitudinal edge, formed by the backing sheet, which is wider than the mat fabric. When the mat is cut to length, the lateral edges have rubber borders, since they correspond to the longitudinal edges of the continuous roll. However the top and bottom cut edges do not have rubber borders, resulting in a mat which is not aesthetically pleasing. It is known to use extruded plastic edging strips at the top and bottom of the cut mat, but such edging strips do not match exactly the rubber borders at the lateral edges, and are not compatible with the mat, causing distortion and rippling. Furthermore, the mats are not launderable, because the plastic strips cannot withstand the heat of the laundering process.
It is an object of the present invention to provide a mat which may be cut to length from a roll, but which is launderable and as aesthetically pleasing as a made-to-measure mat.
According to a first aspect of the present invention there is provided a substantially rectangular mat comprising an upper layer of fabric bonded to a lower backing layer of natural or synthetic rubber, whereby the lower backing layer extends beyond the upper fabric layer to form a border strip at first and second opposite edges of the mat, and whereby the lower backing layer ends flush with the upper fabric layer at third and fourth opposite edges of the mat, each of the third and fourth edges being provided with a moulded strip of synthetic or natural rubber attached to the lower backing layer to form a border strip.
Preferably, the moulded strip is attached to the lower backing layer by adhesive.
Preferably the moulded strip is formed such that the border strips at the third and fourth edges are of substantially the same appearance as the border strips at the first and second edges.
Preferably, the moulded strip includes a thin web portion that is secured beneath the backing layer and a thick web portion that abuts an edge of the backing layer.
According to a second aspect of the present invention, there is provided a method of making a mat comprising the steps of:
providing an elongate roll of mat material comprising an upper layer of fabric bonded to a lower backing layer of natural or synthetic rubber, whereby the lower backing layer extends beyond the upper fabric layer to form a border strip at the longitudinal edges of the elongate roll;
cutting transversely the elongate roll to form a portion of the elongate roll in which the lower backing layer extends beyond the upper fabric layer to form a border strip at first and second opposite edges of the mat, and in which the lower backing layer ends flush with the upper fabric layer at third and fourth opposite edges of the mat;
attaching a moulded strip of synthetic or natural rubber to the lower backing layer to form a border strip at the third and fourth opposite edges of the mat.
Preferably, the moulded strip is attached to the lower backing layer by adhesive.
Preferably, the moulded strip is formed such that the border strips at the third and fourth edges are of substantially the same appearance as the border strips at the first and second edges.
According to a third aspect of the present invention, there is provided a border strip for use in the method according to the second aspect of the invention, the border strip comprising an elongate member of natural or synthetic rubber of uniform cross-section, having a thick web portion and a thin web portion arranged adjacent to the thick web portion to form a generally L-shaped cross-section, the thin web portion being adapted to be secured beneath the backing layer of a mat in use, the thick web portion being adapted to abut the edge of a mat in use.
According to a fourth aspect of the present invention, there is provided a method of manufacturing a border strip according to the third aspect of the invention, the method comprising the steps of:
arranging first and second elongate mould plates in spaced apart relationship with a gap there between, said first mould plate having a cutting edge arranged adjacent to the gap, and said second mould plate being provided with a longitudinal channel in its upper surface extending parallel to and distal from the gap;
introducing fluid rubber into the mould such that the gap is filled with rubber and the rubber extends over the upper surface of the second mould plate and flows into the channel;
allowing the fluid rubber to cure to form a thick web in the gap, a thin web on the upper surface of the second mould plate, and a bead in the channel; and
removing the thick web and thin web from the mould and thereby separating the thin web from the bead in the channel.
Preferably, fluid rubber is introduced into the mould by placing a sheet of uncured rubber on top of the mould and heating the rubber in situ so that it flows into the mould.
Preferably, the rubber is heated in a heated press.
Preferably, the fluid rubber extends over the cutting edge of the first mould plate. Preferably, the excess rubber is removed from the surface of the first mould plate after curing by a cutting action of the cutting edge.
Preferably, the longitudinal channel has a narrow neck. Preferably, the separation of the thin web from the rubber bead is accomplished by the cutting action of a cutting edge provided at the neck of the channel. The thick web and thin web may be lifted from the mould and the separation accomplished by a tearing action.